1. Field of Invention
This invention relates to weight bar end caps, specifically to such end caps which are used for receiving and retaining external weight without the use of a separate collar.
2. Description of Prior Art
Fitness exercise bars that use interchangeable weights to vary resistance have been around for many years and are well known in this field. Most systems use a variation of a weight plate that slips onto either end of a bar and is secured by a locking collar mechanism. These collars do a good job securing the weights to the bar, but they make changing the weight more time consuming. Also, these collars are made of hard materials and offer no protection or cushioning if they are dropped, so damage to sensitive flooring material or injury to the user could result.
Some locking collar devices have been invented to make changing weights simpler and quicker. U.S. Pat. No. 4,817,944 to Anderson et al. (1989) discloses a collar locking device that slides against the weight and when its axis is skewed, frictionally holds the weight in place. U.S. Pat. No. 5,603,680 to Larson (1997) discloses a collar locking device that holds weights in place with springs and a contact base. U.S. Pat. No. 4,773,641 to Metz (1988) discloses a collar locking devise that uses the friction between o-rings within the devise and the greater diameter of the weight bar to retain the weights. All these disclosed devices still make the user attach the device to the bar to secure the weight and detach the device to remove the weight. This is time consuming. Also none of these devices offer any type of cushioning to the weight bar end so if it is dropped it can damage floors or cause injury to the user.
Some inventors have created weight systems that do not use a locking collar devise to secure the weight to the bar. U.S. Pat. No. 5,407,413 to Kupferman (1995) discloses a integrated weight and locking system that helps lock weights together by a simple "press and turn" motion. While this system does not need a collar to secure the weights to the bar, it is a proprietary system and only works as a system; common, inexpensive barbell plates cannot be used. Standard weights plates are ubiquitous but are useless with this system. So gyms and individuals who already use standard weight plate systems couldn't use this system without a substantial investment in this new system, which would be expensive.
Another proprietary system is disclosed in U.S. Pat. No. 5,449,333 to Carter (1995). This system does away with using a collar locking device by the use of grooves in the bar itself and flexible o-rings mounted on the inside surface of the weights. The weights are locked into place by the o-ring fitting into one the grooves along the ends of the bar. Like the above disclosed device, this system only works with components designed for that system. It also suffers from the other disadvantages listed above for U.S. Pat. No. 5,407,413.
All the devices for securing weight to a weight bar heretofore known suffer from one or more of the following disadvantages:
(a) They require the user to attach a locking collar device to secure a weight to a weight bar. Then, the user must detach the device to remove the weight. This adds time and steps to changing the weight on a weight bar. PA1 (b) The materials used in these devices are substantially hard so they offer no cushioning to the end of the weight bar. Thus, if the weight bar is dropped it can damage the floor or injure the user. PA1 (c) They use a proprietary weight and locking system that does not accept common weight plates. Anyone who already has the common style weight would have to replace them with a proprietary system which would be expensive. PA1 (a) to provide an end piece for a weight bar that accepts various weights and restrains them without the use of a collar locking device; PA1 (b) to provide an end piece for a weight bar that cushions the end of the bar so that it cannot dent or scar delicate flooring and helps prevent injury to the user; PA1 (c) to provide an end piece for weight bar that is inexpensive and easy to produce; PA1 (d) to provide a end piece that can be produced in a variety of colors.